The present invention relates to passive target detecting systems and more particularly to target detecting systems with the capability of discriminating against both doppler and continuous wave off-target radars. The present invention is an improvement over the target detecting system disclosed and described in copending application of Erwin I. Abadie et al., Ser. No. 553,344 filed May 24, 1966 for Target Detecting Device. In the above referenced application a system is disclosed which will provide a firing signal at the proper point in the missile trajectory. The circuitry for processing a signal received from an enemy radar target works in conjunction with a phased antenna providing a negative output signal when the target is in a position forward of the critical or cross-over angle and a positive signal output when the target has passed the cross-over angle. If the signal from the antenna is positive, a firing signal is generated thereby initiating firing of the missile warhead. The above described system does not provide for CW radar.